The invention relates to a hydraulically damped tubular rubber spring consisting of an inner tube and an outer tube, both made of hard materials, the outer tube surrounding the inner tube in a spaced relationship. In the clearance resulting from such spacing there is disposed a rubber element that is adhesively mounted both internally and externally and which comprises at least two chambers, arranged in a row in the direction in which the forces are applied, and separated by a partition. These chambers are filled with a liquid and are interconnected through at least one throttle opening, the mouths of which are spaced sufficiently on either side from fronting surfaces so that there is no measurable back-up therein of liquid streams that issue as a result of vibrations.
A tubular rubber spring of this type is known from the European Pat. No. 9,120. In this device the throttle opening is formed by a very narrow duct pressed into the outer circumference of an intermediate tube disposed between the rubber element and the outer tube. The damping properties of this known tubular rubber spring are not fully satisfactory.
Another design of a tubular rubber spring is disclosed in the German published patent application No. 33 43 392. In this case, the throttle opening is disposed in a radial enlargement of the wall of the inner tube and comprises two mouths which are centrally associated with the axis of symmetry, are open in the direction in which the forces act, and are directly in front of the abutment surfaces of the outer tube. With this design, the damping action is far from satisfactory especially in the case of pronounced displacements of the inner tube relative to the outer tube.